When state Del. John G. Gary announced his Republican campaign for county executive in December, he took up incumbent Robert R. Neall's mantle of fiscal conservatism. state Del. Theodore J. Sophocleus hopes to snatch it away.

Mr. Sophocleus, who won the Democratic nomination Tuesday, painted himself yesterday as a fiscal conservative and former corporate manager, better suited to continue the reinvention of county government started by Mr. Neall.

"John is saying 'I'm going to mirror what Bobby did,' " said Mr. Sophocleus, who was narrowly defeated by Mr. Neall in the 1990 general election. "I'm saying, Bobby did a great job, but that was just the beginning. Now, it's time to move and see if what he did works."

Mr. Sophocleus, a former two-term county councilman, said only he has the experience to retool the county Police Department, environmental regulations and schools to meet citizens' demands of more for less.

Mr. Gary, who ran unopposed in the Republican primary, scoffed yesterday at Mr. Sophocleus' self-portrait. Between now and the Nov. 8 general election, Mr. Gary said, "The main thrust of my campaign is going to be, 'Who do you trust running your government, managing its money and its employees?'

"I'm going to point out that when Mr. Sophocleus was on the council, many of the things he says he'll do now, he didn't do then," Mr. Gary said. "The question is, why?"

Mr. Gary will attempt to link Mr. Sophocleus to the administration of former County Executive O. James Lighthizer and will paint that administration as free-spending and wasteful.

"I have an opponent who's telling people he's going to be a fiscal conservative and a good manager, but when he was on the council he was neither," Mr. Gary said.

Mr. Gary will have help in his counterattack.

Robert Schaeffer, head of the Anne Arundel Taxpayers Association, which backed a successful property tax cap two years ago, said, "I don't want Ted Sophocleus to be county executive because I think we will be taking a four-year step" back to the Lighthizer years.

"He was part of the government and now he wants us to pretend like he wasn't. It's visible in his pension."

Mr. Sophocleus, 55, and his wife, who served as his legislative aide for eight years, receive retirement checks totaling more than $900 a month. Mr. Sophocleus voted in 1989 with a unanimous council to improve those benefits.

Although the issue was raised in the Democratic primary, it appeared to have little effect.

"Even though it has been hammered on, I think there is a lot more to it than just his vote to enhance his own pension," said Mr. Gary, 50. "I'm not going to let the pension issue go away."

Although Mr. Sophocleus entered the Democratic primary widely favored, many felt by election day that he was seriously challenged by Robert Agee, vice president of Chaney Enterprises and a former Lighthizer aide.

Mr. Agee, of Crofton, said he may support Mr. Sophocleus in the general election, but was critical of his primary opponent's last-minute tactics.Mr. Sophocleus, a Linthicum resident, sent a Mailgram to 17,000 North County voters urging them to vote for him because he comes from North County. He also promised not to allow the county to build a $27 million jail in Glen Burnie.

"An important theme in my campaign has been to stop the division politics," Mr. Agee said Tuesday night. "It's pitting one part of the county against the other. That telegram is going to come back to haunt him. It was very divisive.

"If I was John Gary, I'd be making 50 copies of that right now."

Mr. Sophocleus said he did not think the letter was divisive.

"The last thing you do in any campaign is a get-out-to-vote mailer, and that's what this is," Mr. Sophocleus said. "I basically told people they had the opportunity to elect a county executive from North County and that they should take it."

Helen Fister, chairwoman of the county's Republican Central Committee, said the Republicans had expected to face Mr. Sophocleus all along.

"It's going to make a very good race," Mrs. Fister said. "It could be a horse race, but I think we have a very good chance of picking up the county executive's office again."

State Sen. Michael J. Wagner, a Ferndale Democrat, said Mr. Sophocleus' decisive primary victory gives him a strong edge over Mr. Gary in a county where the Democrats hold a 3-2 advantage in voter registration.

"I think this campaign will divide along party line more than any other county executive race we've had in the past," said Mr. Wagner, noting that past executives, such as Joseph W. Alton Jr. and Robert Pascal, led bipartisan tickets. "John is more a pure, pure Republican."